Frozen Strawberry Cake

Preheat the oven to 350 degrees F (175 degrees C). Grease and flour a 9x13-inch baking pan.

Mix flour, sugar, baking soda, and salt together in a bowl. Add shortening, sour cream, eggs, and vanilla extract and beat with an electric mixer on medium speed for 3 minutes. Fold in strawberries. Pour into the prepared pan.

Bake in the preheated oven until a toothpick inserted into the center comes out clean, about 40 minutes. Cool on a wire rack for 5 minutes. Run a table knife around the edges to loosen. Invert carefully onto a serving plate or cooling rack. Let cool, about 30 minutes.

While cake cools, pour reserved strawberry juice in a pan and bring to a boil. Mix water and cornstarch together and add to the juice; cook and stir until sauce thickens. Serve over cake.